Composition for removing carbon deposits



Patented Feb. 7, 1933 1 UNITED STATES PATENT OFFICE CHARLES A. THOMASAND cannon.

A. HOCHWALT, OF DAYTON, OHIO, A SSIGNORS TO THOMAS &: HOCHWALTLABORATORIES, INC., 0F DAYTON, OHIO, A CORPORATION OF OHIO COMPOSITIONFOR REMOVING cannon DEPOSITS Ho Drawing.

This invention relates to compounds for removing carbon deposits such asare formed in internal combustion engine cylinders.

One of the principal objects of this invention is to provide a superiorcomposition which is unusually effective in removing such deposits. I

' Another object of the invention is to provide such a composition forremoving such carbon deposits which is quite cheap, has a relativelyhigh boiling point, and has no objectionable deleterious effects uponmetal parts with which it comes in contact, such as the cylinder of aninternal combustion en ine.

till another object of the invention is to provide a composition of thischaracter which serves to maintain the loosened carbon deposits withinan engine cylinder in a condition such as to prevent rattling of theloosened deposits or other objectionable results upon restarting of theengine.-

Other objects and advantages of the invention willbe apparent from thefollowing description and appended claims.

Carbon deposits such as are formed in internal combustion engines arefoundto consist primarily of the following ingredients: (1) road dustwhich consists principally of silica; (2) lubricating oil resulting fromseepage past the piston rings; (3) graphitic carbon which resultsprimarily from crackin of the gasoline andlubricating oil; and (4%oxidized lubricating oil which results from the oxidation of theordinary lubricating oil which has seeped past the piston rings,

. number of complex and undetermined this oil being oxidized at the hightemperatures present in the cylinder and in the presence of oxygen ofthe fuel mixture. The oxidized lubricating oil, which comprises acompounds of carbon, oxygen and hydrogen, forms a resistant hinder orcement which binds the road dust and graphiticcarbon together to holdthem tightly onto the cylin der head, the piston top, and other portionsconfining the combustion space.

Various solvents, such as alcohol and benzol, which for purposes ofdescription are hereinafter termed varnish removing sol- Applicationfiled October 3,

halogen, such as ,ing at least one effective carbon removing compounds.

1929. Serial No. 397,144.

hydrocarbons, have a superior solvent action upon this binder; 'Forexample, we have discovered that the chlorinated naphthalenes, C H CI inwhich a2 represents the number of substituted chlorine atoms, are veryeflective carbon removers. Thus monochlornaphthalene, either alpha orbeta, C H OI, which is an aromatic organic compound containingtwobenzene rings this character. We have discovered that other aromatichydrocarbons containing at least one benzene ring having a substitutedthe chlor-benzene compounds O H CI and the brome-benzene compounds, C HBr are excellent carbon removers, such for example as phenyl chloride OH OI and the dichlorbenzenes C l-L01 Other compounds in thisclassification containing at least one benzene ring and having asubstituted halogen, in which some of the other hydrogen atoms of thebenzene nucleus have been substituted by radicals, such as a methylradical, or phenyl radical are also effective carbon removers. Forexample, the halogenated toluencs such uene C H CH CI, the halogenatedxylenes such as monochlor-xylene C H (CH Cl,

and the halogenated dibenzenes such aschlordiphenyl (OJ-19 015, satisfythe requlrements of carbon removing compounds in accordance with thisinvention.

Other halogenated hydrocarbons containbenzene ring, which have a sidechain including a substituted halogen in the side chain, we havediscovered to be For example, benzal chloride O H CHOl and henzylchloride O H OH Ol, in which the chlorine atom is, oratoms are,connected to the side chain, are good carbon removers.

as monochlor-tolhaving one substituted halogen, is an excellent compoundof Certain of the halogenated hydrocarbons mentioned, such as some ofthe chlorinated naphthalenes, and dichlorbenzenes, are solids atordinary temperatures. In order to place these compounds in a suitableform for use and to make their application easy and more effective,these compounds are preferably dissolved in suitable varnish removingcertain of the pounds for this purpose.

This is quite important, for

solvents, such as various alcohols, ether, acetone, ethyl acetate,benzene, and the like. A very satisfactory varnish removing solvent forthis purpose is a mixture of ethyl alcohol and benzol (commercialbenzene). -W-e find it preferable to use absolute alcohol to insure thesolubility of the desired amount of halogenated hydrocarbons. Thusconsiderably higher percentages of the chlorinated naphthalenes can bedissolved in absolute alcohol than in-95% alcohol, for example. Theproportions of the various constituents may able limits, but it is foundthat more effective results are secured with a substantial portion ofeach of the three constituents, namely, the ethyl alcohol, benzene andthe halogenated hydrocarbon, present.

We have discovered that more effective results are obtained whenchlorinated hydrocarbons having a high boiling point are used,

this preventing excessive evaporation and escape of the carbon removingcomposition when introduced into a heated engine cylinder. Thechlorinated naphthalenes, such as monochlor-naphthalene which has aboiling point of 264 C., provide excellent com- It is found preferableto have rather large percentages of the halogenated hydrocarbon, such asthe chlorinated naphthalene, present in the composition in order toraise the boiling point of the composition as well as to increase thesolvent action upon the resistant binder. The varnish removing solventsfunction not only as a carrier or solvent for the halogenatedhydrocarbons, but also serve to attack the unoxidized lubricating oiland the like of the carbonaceous resinous deposit.

A high boiling point compound such as a chlorinated naphthalene of thecharacter mentioned above not'only functions as a superior solvent forthe oxidized binderof the deposits, but also serves to maintain theloosened carbon deposits within an engine cylinder in a moist or mushycondition. where the 'carbon remover functions in a superior manner asis the case with the present composition to loosen large quantities ofdeposits within an enginecylinder, these loosened particles may resultin objectionable operating conditions upon restarting of the engine ifthey are not maintained moist or in a mushy condition. This isparticularly true in compression engines havin small clearances betweenportions of the piston and heafil or case, if the carbon be variedwithin'considervolatile combustible may the case of highride as well ashigh testgasoline,

between the valves and the head. In such remover is of a character whichpermits the loosened deposits to dry out during standing and before therestarting of the engine, then these dry loosened particles may ambetween the piston or valves and the head to cause objectionableknocking or even fracture of the engine parts when the motor is started.The present compo'sitionis effective to loosen the deposits as well asto insure against such objectionable operating conditions uponrestarting of the engine, for the moist or mushy deposit is free to flowwithin the clearance space which prevents objectionable jamming betweenthe piston or valve and the head.

As an example prepared in accordance with this invention, the followingis mentioned:

of a supemor composition Percent by .volume Monochlor-naphthalene 50Absolute denatured ethyl alcohol 25 Benzol (commercial benzene) 25 Achlorinated benzene such phenyl chloride C H Cl, may be used inconjunctionwith the monoclilor-naphthalene in the above example withgood results. When phenyl chloride is used, ordinary denatured ethylalcohol is satisfactory, and absolute alcohol need not be used to insuresolubility of the desired amount of the halogenated hydrocarbon.

The chlorinated naphthalenes, such as monochlor-naphthalene, arecompounds for use in removing the carbon from engine cylinders, inasmuchas such compounds have a lubricating value in addiquite suitable tiontotheir other properties, so that after 1 use of the carbon remover thedanger of the pistons binding because of solution of the lubricating oilon the cylinder wall is minimized. We have found a. compositioncontaining an admixture of a chlorinated naphthalene such asmonochlornaphthalene with a chlorinated benzene such as phenyl chloridegives very satisfactory results. ere a mixture of one halogenatedhydrocarbon, such as a chlorinated naphthalene, with another halogenatedhydrocarbon of different characteristics, such as phenyl chloride, isused in suitable proportions, superior solvent action upon the resistantbinder is obtained over that produced by either solvent separately, orthe additive efiects of the two solvents when used separately.

In order to ,-insure easy starting of an internal combustion engineafter application of the carbon remover, a quantity of a highly beincorporated in high test the-compositiom- For example,

gasoline functions very satisfactorily for this purpose.

As an example of a composition incorporating monochlor-napthalene andphenyl chlohich has 'solvcnt action is ed claims.

ing is mentioned Per cent by volume Halowax oil (monochlor-naphthalene)2O Phenyl chloride Benzol 20 Denatured ethyl alcohol 20 High testgasoline "'20 In the above example using equal proportions of the twochlorinated aromatic hydrocarbons of different characteristics asuperior obtained. Where the other constituents are maintained in thesame proportion, one of the chlorinated aromatic hydrocarbons may besomewhat increased in proportion as the other chlorinated aromatichydrocarbon is correspondingly decreased wit portionsof theotherconstituents are altered, the combined proportions of the twochlorinated hydrocarbons may be altered while maintaining approximatelythe same ratios of these two constituents with goodresults.

In using the composition of this invention to remove carbon depositsfrom an internal combustion'enginc, the engine is first run until it isquite hot. Then the carbon remover is introduced into the. cylinder,either by pouring throughthe spark plug openin or by drawing, it intothe cylinder througi the .intake manifold, care being taken to preventescape of the solvent through the exhaust ports. Generally about 20 toc. c. are added per cylinder. The motor is then allowed to stand forsome time, preferably about six hours or over night, during which timethe composition acts u on the binder and loosens the insoluble carbonand road dust free. I started-rand allowed to run a short time, theblast serving to blow the loosened material out through the exhaust.

Reference is herein made to our 00- endmg application, Serial No.301,702, filed discloses and claims August 23, 1928, which a carbonremover composition containing in conjunction with a highly effectivesolvent ingredient, asufiicient quantity of a high boiling heatresisting material to maintain loosened carbon deposits in a moistcondition. In the present case, there is disclosed and claimed such acarbon removing composition containing a high boilin heat resisting inredient which has the ouble function 0 being aneffective solvent for thedeposits, posits in a moist condition. 7

While the compositions herein described constitute preferred embodimentsof the invention, it is to be understood that the invention is notlimited to these precise compositions and that'changes ma thereinwithout de artin from t e scope of the invention whic good results ;-orwhere-the combinedpro ed benzene.

In testimony whereof we hereto aflix our What is claimed is Acomposition for removing carbon deposits from engine cylinderscomprisinga. so-

lution of a chlorinated naphthalene in ethyl alcohol and benzol. g

2. A composition for removing carbon deposits from engine cylinderscemprisin a. mixture containing a halogenated napht alene and ahalogenated benzene giving a superior solvent action therewith.

3. A composition for removing carbon deposits from engine cylinderscomprising a. chlorinated naphthalene and a chlorinated benzene.

4. A composition fcrremoving carbon do posits from engine cylinderscomprising a chlorinated naphthalene, achlorinated benzene, benzolandethyl alcohol.---

' 5. A composition for removing carbondeposits from en ine cylinderscomprisingmonochlor-naphtha ethyl alcohol and gasoline.

ene, phenyl chloride, benzol,

6. A composition for removing carbon deposits from engine cylinders,comprisin a mixture containing an organic solvent which dissolveslubricating oil, and'a pro rtion of a halogenated aromatic hydrocar nSuficient to effectively soften carbon deposits. A compositionforremoving carbon deposits from engine'cylinders, comprising a mixturecontaining as essential ingredients halowax carbon in proportionssuflicient to efl'ect'ively soften the carbon deposits, v

8. A carbon removing composition comprising a halogenated aromatichydrocarbon. 9. A carbon removin composition com carbon removingcomposition comprising as an essential signatures.

CHARLES A. CARROLL A.

THOMAS. HOQHWALT.

ingredient a chlorinatoiland anotherhalogenated hydro prising as anessential ingredient a. chlorinated naphthalene.

The motor is then,

be made is de fled in. the append-

